Question

Latent heat of ice is
(A) $336kJk{g^{ - 1}}$
(B) $663kJk{g^{ - 1}}$
(C) $363kJk{g^{ - 1}}$
(D) $636kJk{g^{ - 1}}$

Answer 1

Hint: The heat required for the phase change of water from solid to liquid or gas, liquid to solid or gas, at constant temperature is called the latent heat of the water. Latent heat can also be expressed as the amount of heat released or absorbed to change the state of a substance without changing its temperature.

Complete step by step answer:
Latent heat can be defined as the amount of energy that is either released or absorbed by a body or any thermodynamic system, during a process in which its phase/state changes, while the temperature of the body remains kept constant.
The specific latent heat of fusion of ice is equated to $334kJ/kg$.

So, the correct answer is “Option A”.

Additional Information:
(i) The S.I. unit of latent heat is the joule ($J$).
(ii) Latent heat of a body can be of two types i.e. latent heat of fusion and latent heat of vaporization. These represent the direction of flow of heat on changing from one phase to another. When an object changes from solid to liquid then the heat involved is the latent heat of fusion and when the object changes from liquid to gas then the heat involved is the latent heat of vaporization.
(iii) When a substance gets condensed at a constant temperature and pressure the latent heat involved is the latent heat of fusion and when a substance gets vaporized then the latent heat involved is the latent heat of vaporization.

Note:
It should be kept in mind that the Latent heat is energy transferred in a process without changing the temperature of the substance. Apart from latent heat we also have sensible heat in which along with the transfer of energy, temperature change also occurs.